This invention relates to construction of fences, in particular but not only to systems for construction of pool fences or balustrades. The systems might also be suitable for other structures which in some cases have picket-like features in common with fences, such as ladders or walls.
Pool fences are constructed in a wide variety of ways. A standard pool fence typically has a number of aluminium panels that are formed separately and then placed in position together. Each panel has two or more horizontal rails that support a series of vertical pickets. The panels are assembled by passing the pickets through apertures in the rails. Each picket is then usually welded or crimped to the rails and the assembled structure is painted. The rails and pickets come in many forms and may be assembled in a wide variety of structures.
The existing methods of construction require each picket to be individually handled and fastened to the rails. Each panel typically has 20-30 pickets so the methods are generally slow with a significant cost of manual labour. The need to paint the panel after the pickets have been fastened to the rails can also be a disadvantage. Structural weaknesses are sometimes experienced in panels where the pickets do not extend beyond the top rail. In these systems the top ends of the pickets lie within the top rail and can be difficult to fasten sufficiently strongly to the rail.